Wireless telephones are widely used across all socioeconomic groups in the United States. Most adults and teens, and many children, have their own wireless devices that they use for telephone calls, email, Internet access, etc. As a result, an increasing number of households are becoming “wireless-only” as homeowners see their traditional wired telephone service as redundant and/or unused.
The increasing use of wireless devices for voice and other communications can present a problem for the law enforcement community because wireless telephone numbers cannot be easily matched to a physical address as was traditionally possible with wired or landline telephone numbers. The FCC's local number portability (LNP) rules allow users to switch telephone service providers and keep their existing telephone number. This can make it difficult to identify the current service provider for a particular wireless device using just the telephone number. The telephone number being used by a wireless device may have been ported among two or more different carriers since it was first assigned. Accordingly, in order to obtain call and billing records for a wireless device that is relevant to an investigation, law enforcement must first identify the relevant service provider. Then, an investigator must obtain the proper warrant to request the records from the service provider.
After call and billing records for a telephone number of interest are obtained, the investigator may only have a billing address for the wireless device. Unlike traditional landline telephones, the wireless device may be used to make telephone calls from any location across the country or the world. So the billing address is not necessarily helpful in identifying the current location of the wireless device. Detailed call records from a service provider may indicate locations for past telephone calls, such as by identifying a cellular network tower that supported a particular call. However, such historical location information is of limited use because the wireless device user has likely moved from the location of those past calls.